package com.itheima.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否已经完成登录
 * 过滤器
 */
@WebFilter(filterName = "loginCheckFilter", urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();


    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1、获取本次请求的URI
        String requestURI = request.getRequestURI();
        log.info("拦截到请求：{}", request.getRequestURI());


        //定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login",
                "/doc.html",
                "/webjars/**",
                "/swagger-resources",
                "/v2/api-docs"
        };

//2、判断本次请求是否需要处理
        boolean check = check(urls,requestURI);

//3、如果不需要处理，则直接放行
        if(check){
            log.info("直接放行{}", request.getRequestURI());
            filterChain.doFilter(request, response);
            return;
        }
//4、判断登录状态，如果已登录，则直接放行
        if(request.getSession().getAttribute("employee") != null){
            log.info("已登录,用户id为{}", request.getSession().getAttribute("employee"));
            Long empId = (Long)request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);
            filterChain.doFilter(request, response);
            return;
        }
        //4-2、移动端判断登录状态，如果已登录，则直接放行
        if(request.getSession().getAttribute("user") != null){
            log.info("已登录,用户id为{}", request.getSession().getAttribute("user"));
            Long userId = (Long)request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);
            filterChain.doFilter(request, response);
            return;
        }
//5、如果未登录则返回未登录结果,通过输出流方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        log.info("未登录{}", request.getRequestURI());
        return;

        //filterChain.doFilter(request, response);//放开过滤
    }

    /**
     * 判断url是否与可放行url匹配
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls,String requestURI) {
        for (String url : urls) {
            if (PATH_MATCHER.match(url, requestURI)) {
                return true;
            }
        }
        return false;
    }
}
